Name: Gluten-Free Funfetti Birthday Cake
Prep time: 30 min
Cook time: 30 min
Total time: 60 min
Ingredients: 3 cups gluten-free flour (Use King Arthur's Measure for Measure for best results.); 2 cups sugar; 1 cup unsalted butter (2 sticks, softened.); 4 large eggs (Room temperature, for better mixing.); 2 large egg whites (Room temperature, for better mixing.); 3/4 cup whole milk (Room temperature.); 1/4 cup buttermilk (Room temperature.); 1/3 cup sour cream; 1 tablespoon gluten-free baking powder (Plus 2 teaspoons.); 3 teaspoons vanilla extract; 3/4 to 1 cup sprinkles (Preferably gluten-free.); 1 cup unsalted butter (2 sticks, softened.); 4.5 to 5 cups sifted confectioners sugar (Amount varies for desired thickness.); 1/3 cup heavy whipping cream (Adjust for consistency.); 2 teaspoons clear vanilla extract (To keep frosting white.)

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The Afternoon This Recipe Stole My Heart

A few years ago I promised my niece a real birthday cake, the kind that leaves a little sparkle on your clothes and a big grin on your face. I wanted something cheerful and forgiving, because gluten is a no-go in our house. The result was my Gluten-Free Funfetti Birthday Cake, a pillowy white cake freckled with colorful sprinkles and wrapped in glossy buttercream. If you are dreaming of a cake that smells like warm vanilla and childhood, this is it. If you want extra party inspiration while you bake, I once paired this cake with a full number-shaped centerpiece and got ideas from a stunning number cake I saw online.

When I say freckled with sprinkles, I mean the kind that peek through the crumb and catch the light when you slice a piece. It calls for 3 cups gluten-free flour (360g) — I use King Arthur’s Measure for Measure so the texture comes out reliably — and 2 cups sugar (400g). The batter gets richness from 2 sticks butter (1 cup 227g), and additional moistness from 4 large eggs plus 2 large egg whites. For the milk components I use 3/4 cup whole milk and 1/4 cup buttermilk, and then fold in 1/3 cup sour cream for silkiness. To leaven, I use 1 tablespoon plus 2 teaspoons gluten-free baking powder and 3 teaspoons vanilla extract. Lastly, the party: 3/4 to 1 cup sprinkles, preferably ones labeled gluten-free so they do not color the batter oddly.

The Secret Behind Perfect Gluten-Free Funfetti Birthday Cake

I learned early that the secret is twofold: measure by weight and do not overwork the batter. Start by warming your oven to 350 degrees Fahrenheit and preparing two 8 or 9 inch cake pans, greased and lined with parchment. In my mixing bowl I cream the 2 sticks of butter with the 2 cups sugar until the mixture is pale and airy; it will smell like vanilla clouds. Then I add the eggs one at a time and the egg whites, each incorporated fully before the next. The eggs give structure and lift without making the crumb rubbery, which is a danger with some gluten-free flours.

Combine the dry bits — the 3 cups gluten-free flour (360g) and the 1 tablespoon plus 2 teaspoons gluten-free baking powder — and sift or whisk them together so they are light. Alternate adding the dry mix and the wet milks: add a third of the dry, then half of the 3/4 cup whole milk mixed with 1/4 cup buttermilk, then more dry, then the 1/3 cup sour cream, finishing with the last of the dry mix. Stir only until combined. At this stage you fold in the sprinkles gently; I use 3/4 to 1 cup depending how spotted I want the cake to be. A quick tip: if you toss sprinkles in a tablespoon of flour before folding them in they are less likely to sink to the bottom.

Pour the batter into pans and gently tap them on the counter to level. Bake for about 25 to 30 minutes if using 9 inch pans, or 30 to 35 minutes for 8 inch pans. How do you know when it’s done right? A toothpick or skewer inserted in the center should come out with a few moist crumbs but not raw batter, and the top should spring back when pressed lightly. Let the cakes cool in their pans for 10 minutes, then turn them out onto a rack to cool completely before frosting. I cannot stress enough that frosting a warm cake is a recipe for sliding frosting or a melty mess.

Making the Buttercream Icing and Assembling

For the frosting I make a classic, spreadable buttercream that stays white and holds its shape. I beat 1 cup unsalted butter (2 sticks) until soft and a bit billowy, then gradually add 4.5 to 5 cups sifted confectioners sugar until it becomes thick. To loosen it, I add 1/3 cup heavy whipping cream and 2 teaspoons clear vanilla extract, which keeps the frosting a pristine white instead of yellow. If you want a slightly stiffer frosting for piping, use the higher end of the sugar amount. If you want it more ribbon-like for spreading, add a splash more cream.

When assembling, I level the cakes if they domed, then put a generous dollop of buttercream between the layers. I chill the stacked cake for 15 minutes so the crumb layer firms up, then add another thin coat to seal in crumbs before applying the final, smooth layer. For a playful finish I press extra sprinkles around the sides and on top. One of my tips is to keep a bench scraper or offset spatula warm under hot water and dry it before smoothing the frosting; the heat helps create a clean edge.

A Few Things I’ve Learned

I have made this cake for small family breakfasts and large backyard parties, and a few tricks have stuck. First, room temperature eggs and butter make a huge difference. Cold butter makes creaming and emulsification take forever. Second, if your gluten-free flour blend is not Measure for Measure, try whisking in an extra tablespoon of milk or reducing the flour slightly; blends behave differently. Third, when adding sprinkles, choose ones that are not heavily dyed if you want a pastel crumb rather than neon speckles.

If you plan to make the cake ahead of time, it stores nicely. Once frosted, keep it in an airtight cake box or covered with a dome in the refrigerator for up to four days. I also wrap cooled layers tightly in plastic and freeze them for up to three months; thaw in the refrigerator overnight before frosting. When serving, this cake pairs beautifully with a cup of cold milk, a scoop of vanilla ice cream, or even a simple bowl of fresh berries for balance. If you are considering a dessert table, I often put this cake next to bite-sized sweets like macarons for color contrast, inspired by the pretty pairing I learned from a guide to making birthday cake macarons.

Ways to Make It Your Own

Variations are easy. For a lemony twist, fold in a teaspoon of lemon zest and reduce the vanilla by half. For a chocolate-speckled version, add 1/2 cup mini chocolate chips but toss them in a little flour first. If you want dairy-free, swap the milk, buttermilk, and sour cream for unsweetened almond milk and dairy-free yogurt; the texture will be slightly different, but still celebratory.

If you are pairing this cake with other desserts or want to theme a party, try serving it alongside a richer option like a banoffee birthday cake to give guests a choice of light and indulgent, something I did once when my family could not agree on a single flavor and it was a hit, especially because the palates were so different. I actually borrowed some topping ideas from a brilliant banoffee birthday cake I had bookmarked.

If you prefer cupcakes, this batter scales down beautifully; I use the same recipe to make chocolate and vanilla birthday cupcakes when we need handheld treats for a crowd, and the method stays the same for mixing and baking times adjusted for smaller tins as explained in a recipe for chocolate and vanilla birthday cupcakes.

Conclusion

If you want another take on a gluten-free confetti cake for comparison, I used ideas that reminded me of the version over at Eat With Clarity’s gluten free birthday cake when I first started experimenting. For a more technical deep dive into gluten-free confetti cake ratios and alternative flour blends, this Best Gluten-Free Confetti Cake Recipe was a helpful reference while I tuned my own measurements.

Baking this cake is one of my favorite ways to celebrate because it is forgiving, colorful, and reliably joyful. The first bite should be soft and tender, with little pop of sprinkle and the scent of vanilla that makes everyone forget about gluten at the table.